Back in 2003, Jeff Garzik announced the availability of "a new SCSI driver." That driver was, in fact, the libata subsystem, which was to be the foundation for serial ATA support in Linux. In the process, however, Jeff had thought a bit about supporting the current parallel ATA (PATA) drives, but that was not really his goal: Note that PATA in my driver is only an afterthought. The main area of focus, now and in the future, is SATA.
In the last three years, the parallel ATA drives that most of us use have continued to be driven by the old IDE driver subsystem. Some of this code dates back to the beginning of Linux; since then it has been maintained by a substantial list of people, a number of whom are widely held to have been driven insane by the experience. The current maintainer, Bartlomiej Zolnierkiewicz, has kept a rather low profile for some time now; he signed off no patches in either of the 2.6.17 or upcoming 2.6.18 kernels. Not much has been happening in the IDE area.
http://www.linuxworld.com/news/tech/2006/092006-parallel-ide.html